Synergistic radiation protective pharmaceutical compositions

ABSTRACT

The invention is directed to a synergistic radiation protective pharmaceutical composition comprising 50 to 350 parts by weight of aminoalkyl-thiol-derivatives of the general formula II ##STR1## wherein R 3  stands for hydrogen, or carboxamidino 
     R 4  stands for hydrogen or carboxy, 
     B represents hydrogen or carboxamidino with the restriction that at least two of R 3 , R 4  and B stand for hydrogen-- 
     or a pharmaceutically acceptable acid addition salt thereof, 0.2 to 2 parts by weight of ω-acylamino-alkane-derivative of the general formula ##STR2## wherein R 1  stands for hydrogen, C 1-4  alkanoyl, aroyl or aryl-(C 1-4 )-alkoxy-carbonyl, 
     R 2  stands for hydrogen, or carboxy optionally esterified by C 1-4  alkoxy or aryl-(C 1-4 )alkoxy, 
     A stands for --SO 2  OH or --O--PO(OH) 2 , 
     n stands for 1, 2 or 3 and 
     m stands for 2, 3 or 4--or a pharmaceutically acceptable salt thereof, 
     and pharmaceutically acceptable carriers, diluents and/or solvents, and/or other formulating excipients.

This application is a continuation of application Ser. No. 133,832,filed Mar. 25, 1980, now abandoned.

FIELD OF THE INVENTION

The present invention relates to synergistic radiation protectivepharmaceutical compositions and a process for the preparation thereof.

BACKGROUND OF THE INVENTION

It is known that aminoalkyl-thiol derivatives of the formula II ##STR3##containing a sulfhydryl group--wherein R³ is hydrogen or carboxamidino

R⁴ is hydrogen or carboxy and

B is hydrogen or carboxamidino, provided that at least two of R³ and R⁴and B are hydrogen-

and pharmaceutically acceptable acid addition salts thereof are the mosteffective radiation-protective substances known heretofore (Knoll J.,Gyogyszertan, Medicina, 1965, page 540). As examples for the abovesubstances cysteine, cysteamine,aminoethyl-isothiuronium-chloride-hydrochloride,aminoethyl-isothiuronium-bromide-hydrobromide andmercaptoethyl-guanidine may be mentioned. Though the radiationprotective activity of the above substances is significant in animaltests, the practical therapeutic utilization thereof is rather difficultbecause of the toxicity of their effective dose or because thiseffective dose is rather close to the toxic range.

Some of the characteristics of some most important radiation protectiveactive ingredients are shown in Table 1.

                  TABLE 1                                                         ______________________________________                                                                Radiation                                                                     protective                                                           LD.sub.50 p.o.                                                                         dose      Therapeutic                                 Active ingredient                                                                            mg./kg.  mg./kg.   index                                       ______________________________________                                        cysteine-hydrochloride                                                                       2500     1900      1.31                                        aminoethyl-isothiuronium-                                                                    1200     1000      1.20                                        bromide-hydrobromide                                                          aminoethyl-isothiuronium-                                                                     710      400      1.78                                        chloride-hydrochloride                                                        mercaptoethyl-guanidine                                                                       350      200      1.75                                        ______________________________________                                    

The data of the table show that the toxic and therapeutic doses areclose to each other.

With the increasing use of radioactive isotopes the probability ofradiation injuries increases as well. As a consequenceradiation-protective pharmaceutical compositions are needed more andmore. In this field both compositions suitable for curing radiationinjuries and compositions suitable for treating humans or animals priorto irradiation in order to increase the tolerated dose by the patientsfor cases of higher radiation doses are desired.

DESCRIPTION OF THE INVENTION

It has been surprisingly found that a combination of known aminoalkylthiol derivatives or acid-addition salts thereof of the formula II withknown ω-acylamino-alkane-derivatives of the formula I ##STR4## whereinR¹ is hydrogen or C₁₋₄ alkanoyl, aroyl, aryl(C₁₋₄)-alkoxy-carbonyl,

R² is hydrogen or a carboxy group which can be esterified witharyl-(C₁₋₄)alkoxy,

A is --SO₂ OH or --O--PO(OH)₂,

n is 1, 2 or 3 and

m represents 2, 3 or 4

or a pharmaceutically acceptable salt thereof (Belgian PatentSpecification 828 546 and 854 347) possesses unexpected synergisticactivity and even if compounds of the formula II are used in a lesstoxic dose a good radiation protective effect is obtained.

Some representatives of the compounds of the formula I areγ-glutamyltaurine, γ-glutamylhomotaurine, γ-glutamylcholamine phosphate,γ-aspartyltaurine, β-aspartylhomotaurine, β-aspartylcholamine phosphate,aminobutyryltaurina, aminobutyrylcholamine phosphate andaminobutyrylhomotaurine aminobutyryltaurine, aminobutyrylhomotaurine,aminobutyrylcholamine sulfate, aminoisobutyryltaurine,aminoisobutyrylhomotaurine or aminoisobutyrylcholamine phosphate.

The synergistic radiation protective pharmaceutical compositionsaccording to the invention contain 0.02 to 2 parts by weight of acompound of the formula I or a salt thereof and 50 to 350 parts byweight of the aminoalkyl-thiol derivative of the formula II or a saltthereof, and the conventionally used carriers, diluents, optionallycoloring-, flavoring-, stabilizing- and/or formulating agents.

The dosage units, such as tablets, capsules, suppositories, injectablesolutions or infusions contain preferably 100 to 200 mg. of the compoundof the formula II or a salt thereof and 0.01 to 2 mg. of the compound ofthe formula I or a salt thereof.

The pharmaceutical compositions may be prepared by using formulatingexcipients, such as solid, liquid and semi-liquid carriers, such asmethyl cellulose, starch, various sugars, e.g. lactose, sucrose, sugaralcohols, such as sorbitol, mannitol and as lubricants e.g. magnesiumstearate, talc, calcium stearate etc. may be used. As liquid carrierswater, lower alcohols may be used alone or in combination with eachother or with the carriers mentioned above. The suppository masses areused as semi-liquid carriers for the preparation of suppositories.

The compositions may further contain stabilizers, fungicidal agents,antioxidants, aromas, flavoring agents, pH-adjusters, osmotic pressurecontrolling components, such as various buffers and sodium chloride.

The tablets prepared from compositions according to the invention may becoated with shellac, which may optionally be suitably colored, and thusintestino-solvent tablets are obtained. The same effect may be achievedby granulating the active ingredients and other necessary additives andby enclosing the obtained granules into capsules which resist thegastric acid, dissolve in the alkaline medium of the intestinal tract orby coating the obtained granules with a suitable coating.

The synergistic pharmaceutical compositions may also be prepared in theform of lyophilized injectable compositions containing the activeingredient combination in the form of a solid powder mixture. Theinjectable solution is prepared prior to administration by methods knownper se from the compositions mentioned above by using a solvent, such assterile water, or physiological saline solution.

The synergistic activity of the active ingredient combinations is shownin Table 2. Experiments are carried out in mice. Irradiation was carriedout with X-ray (rtg) and with gamma rays obtained from ⁶⁰ Co isotope.Survival was observed on the 30th day after irradiation and expressed byusing survival coefficient "S" according to Kaluszyner. (Rad. Res., 27,518, 1961). Mice were treated intraperitoneally.

                  TABLE 2                                                         ______________________________________                                        Treatment        Irradiation    Survival                                      physiological    rtg (R) gamma (rad)                                                                              %   "S"                                   ______________________________________                                        physiological    630                 0  0.30                                  saline                                                                        physiological            900         0  0.34                                  saline                                                                        physiological    800                 0  0.24                                  saline                                                                        physiological            1100        0  0.20                                  saline                                                                        140 mg./kg. AET + Litoralon                                                                    630                56  0.48                                  100 μg/kg.                                                                 140 mg./kg. AET + Litoralon                                                                             900       67  0.80                                  100 μg/kg.                                                                 140 mg./kg. AET + Litoralon                                                                    800                48  0.40                                  100 μg./kg.                                                                140 mg./kg. AET + Litoralon                                                                            1100       51  0.78                                  100 μg./kg.                                                                140 mg./kg. AET + Litoralon                                                                    630                68  0.82                                   1 mg./kg.                                                                    140 mg./kg. AET + Litoralon                                                                             900       71  0.89                                   1 mg./kg.                                                                    140 mg./kg. AET + LItoralon                                                                    800                54  0.40                                   1 mg./kg.                                                                    140 mg./kg. AET + Litoralon                                                                            1100       61  0.75                                   1 mg./kg.                                                                    ______________________________________                                    

In the Table 3 survival and factor "S" of the mice treated only with AETare shown for the sake of comparison. The Table 3 shows that 140 mg./kg.of AET alone substantially does not give any radiation protection.

                  TABLE 3                                                         ______________________________________                                        Treatment     Irradiation     Survival                                        i.p.          rtg (R)  gamma (rad)                                                                              %     "S"                                   ______________________________________                                        140 mg./kg. AET alone                                                                       630                 15    0.39                                  "                       900       5     0.37                                  "             800                 0     0.27                                  "                      1100       0     0.28                                  ______________________________________                                    

Similar good results may be obtained as according to Table 2 byemploying other compounds of the formula I. The results are shown inTable 4.

                  TABLE 4                                                         ______________________________________                                        Treatment      Irradiation   Survival                                         i.p.           gamma (rad)   %      "S"                                       ______________________________________                                        140 mg./kg. AET +                                                                             900          60.7   0.71                                      100 μg./kg GABA-T                                                          140 mg./kg. AET +                                                                            1100          39.8   0.38                                      100 μg./kg GABA-T                                                          140 mg./kg. AET +                                                                             900          61.0   0.75                                      100 μg./kg. GABE-E                                                         140 mg./kg. AET +                                                                            1100          38.6   0.35                                      100 μg./kg. GABE-E                                                         ______________________________________                                    

Abbreviations in the Tables are as follows:

AET=aminoethyl-isothiuronium-chloride-hydrochlorideLitoralon=γ-glutamyl-taurine

GABA-T=γ-aminobutyryl-taurine

GABA-E=γ-aminobutyryl-ethanolamine-phosphate

140 mg./kg. AET dose used according to the above tables is the half ofthe radiation protective dose used in mice i.p.

                  TABLE 5                                                         ______________________________________                                        Radiation-protective activity of a combination of Litoralon                   and mercapto alkyl amine with irradiation being carried out                   with cobalt 60 gamma.                                                         Dose ouput: 55.5 rad/min.                                                     20 animals in each group.                                                     Test substance  Radiation Survival %                                          and dose        dose      30. day   "S"                                       ______________________________________                                        Control         LD.sub.50/30                                                                            50.0      0.61                                      physiological saline                                                          solution: 0.5 ml.                                                             Control         LD.sub.100/30                                                                           .0.       0.28                                      physiological saline                                                          solution: 0.5 ml.                                                             Litoralon 100 μg/kg. +                                                                     LD.sub.50/30                                                  1000 mg/kg.     cysteine  100.0     1.0                                       Litoralon 100/μg./kg. +                                                                    LD.sub.100/30                                                                           66.7      0.88                                      1000 mg/kg. cysteine                                                          Litoralon 100 μg./kg. +                                                                    LD.sub.50/30                                                                            70.1      0.89                                      cystamine 150 mg./kg.                                                         Litoralon 100 μg./kg. +                                                                    LD.sub.100/30                                                                           83.3      0.91                                      cystamine 150 mg./kg.                                                         Litoralon 100 μg./kg. +                                                                    LD.sub.50/30                                                                            100.0     1.0                                       cystamine 150 mg./kg.                                                         Litoralon 100 μg./kg. +                                                                    LD.sub.100/30                                                                           89.0      0.92                                      cystamine 150 mg./kg.                                                         ______________________________________                                    

The synergistic radiation protective pharmaceutical compositions may beemployed not only prior to irradiation but after irradiation as well. Inlatter case the radiation injuries of the central nervous system and ofthe intestinal mucosa are favorably influenced. The decrease of outputand the occurrance of muscle coordination disorders are inhibited orremedied by the compositions as shown by the animal-tests carried out ona rotating and standing rod. Opticovestibular injuries (nistagmustendency) are controlled.

SPECIFIC EXAMPLES

Further details of the invention are illustrated by the followingExamples, which serve merely as illustration and not for restriction.

EXAMPLE 1

Tablets are prepared having the following composition: 200 mg.cysteamine-hydrochloride

0.1 mg. γ-glutamyl-taurine

120 mg. mannitol

20 mg. magnesium stearate

100 mg. wheat starch

EXAMPLE 2

Tablets are prepared having the following composition:

100 mg. aminoethyl-isothiuronium-chloride-hydrochloride

0.2 mg. γ-aminobutyryl-ethanolamine-phosphate

100 mg. mannitol

50 mg. methyl cellulose

50 mg. wheat starch

15 mg. magnesium stearate

10 mg. talc

EXAMPLE 3

Tablets are prepared having the following composition:

220 mg. cysteine-hydrochloride

0.5 mg. γ-aminobutyryl-taurine

100 mg. starch

50 mg. sorbitol

10 mg. talc

15 mg. magnesium stearate

EXAMPLE 4

Tablets are prepared having the following composition:

100 mg. aminoethyl-isothiuronium-chloride-hydrochloride

1 mg. γ-glutamyl-ethanolamine-phosphate

100 mg. methyl cellulose

100 mg. starch

10 mg. talc

10 mg. magnesium stearate.

Tablets are prepared as follows:

The compound of the formula II is dissolved in water and starch ofPharmacopoea quality is wetted with the above solution and the mixtureis homogenized in a kneading machine and dried. The compound of thegeneral formula I is mixed with methyl cellulose and/or sorbitol and/ormannitol in a powder homogenizer, whereafter the dry homogenizate andthe lubricant are added and the mixture is repeatedly homogenized. Drygranules and tablets are pressed.

EXAMPLE 5

Tablets prepared according to Examples 1 to 4 are coated with shellac ina mixing vessel. Thus intestinosolvent tablets are obtained. Shellac maybe replaced by Eudragit or polyphenoxy acetic acid.

EXAMPLE 6

A powder homogenizate is prepared fromaminoethyl-isothiuronium-chloride-hydrochloride and γ-L-glutamyltaurineat a ratio of 100:1 parts by weight. A sterile powder homogenizate isfilled into powder ampoules in portions of 101 mg. and the ampoules aresealed. 5 ml. aqua bisdestillata pro injections are used to prepareinjectable solutions.

The sterile powder homogenizate is prepared by dissolving the activeingredients under aseptic conditions in sterile, apyrogenic, distilledwater, by filtering the solution to get a germ-free and fibre-freesolution followed by lyophilization. Sterile lyophilizates are admixedwith each other in the given ratio. Alternatively the active ingredientsmay be dissolved in a mixed state and the mixture may be filtered toyield a fibre-free and germ-free solution, the solution is filled intothe powder ampoules and lyophilized.

EXAMPLE 7

One proceeds as described in Example 6 but cysteamine-hydrochloride andγ-aminobutyryl-taurine are used in a ratio of 100:1.

EXAMPLE 8

One proceeds as described in Example 6 but cysteine-hydrochloride andγ-aminobutyryl-ethanolamine-phosphate are used, in a ratio of 100:1.

EXAMPLE 9

Suppositories are prepared by admixing 100 mg. ofaminoethyl-isothiuronium-chloride-hydrochloride and 0.1 mg. ofγ-L-glutamyl-taurine in 2 g. of Witepsol W (suppository basic material,manufactured by Dinamit Nobel, Germany).

EXAMPLE 10

Suppositories are prepared by admixing 200 mg. ofcysteamine-hydrochloride with 0.05 mg. ofγ-aminobutyryl-ethanolamine-phosphate in 2 g. of cocoa butter.

We claim:
 1. A synergistic, radioprotective pharmaceutical compositioncomprising 1400 parts by weight of aminoethyl-isothiuronium chloridehydrochloride or aminoethyl-isothiuronium bromide hydrobromide to 1 partby weight of gamma-glutamyl-taurine, and a pharmaceutically acceptablecarrier, diluent or solvent, or a formulating excipient.